One of the most intriguing figures in American music these days is a giant clown with a tiny gold crown atop his head and a perpetually pained expression fixed upon his face. His name is Puddles, and he can croon like an angel who listens to a ton of Nick Cave.

Just ask the audience of NBC's America's Got Talent, where Puddles has been performing to accolades this summer. He made his first appearance quietly lurking onto the stage, carrying a Diogenes-style lamp in one hand and a suitcase emblazoned with "Puddles Pity Party" in the other.

He stepped behind the microphone. An unseen piano played a few measures. And then he began to sing.

"Party girls don't get hurt/ Can't feel anything," he intoned. "When will I learn/ I push it down, push it down…"

The number, of course, was a cover of Sia's "Chandelier," but it had nothing of the original's auto-tuned modernity. In Puddles' hands, it became a bleeding torch song, something out of the movie Cabaret, maybe, or perhaps a piano bar—but nothing likely to have been written or performed in the 21st century.

"Originality at its best," Simon Cowell gushed.

In fact, Puddles is part of an increasingly popular online community of artists who have fused 21st century songwriting to Tin Pan Alley styles to create something that feels both fresh and classic. Together with sometime collaborator Scott Bradlee and a cast of former American Idol contestants and wannabe lounge singers, and backed by a rotating group of top-notch musicians, they're taking reviving seemingly dormant musical traditions for a new era.

In other words: The Great American Songbook is alive and well and living on YouTube.

What's that mean? Well, take this version of "Sweet Child O' Mine, for instance, which features a brassy-voiced woman belting out the tune in a shambling New Orleans style.

"It's a blues song," says Scott Bradlee, who covered the tune on YouTube for his Postmodern Jukebox project. Their version has more than 9 million views to date. "When you strip it away from Axl Rose, it's a very simple song. I started with the lyrics, brought in a band that reflected 1920s New Orleans, brought in a singer who sounded like Bessie Smith. You're acutely aware it's Guns n' Roses, but it sounds like a brand new song."

That process of reinvention and reinterpretation actually defined the early 20th-century era of music-making known as "the Great American Songbook." (The label reputedly dates to a 1972 album by Carmen McRae.) An opera by George Gershwin, like "Porgy and Bess," evolved into jazz masterpieces by Miles Davis, Louis Armstrong and Ella Fitzgerald, Ray Charles and many, many more artists; a song like "My Funny Valentine"—which got its start in a Broadway musical—became standards for Chet Baker, Frank Sinatra, and (yes) Ella Fitzgerald again, appearing on more than 1,300 albums and counting.

"There was this canon or repertoire of classic songs that can be interpreted and reinterpreted," said Ben Yagoda, who wrote about the era in his book The B-Side: The Death of Tin Pan Alley and the Rebirth of the Great American Song.

Yagoda's tome suggests the Great American Songbook era was defined by two features: Great melodies—songs propelled more by musicians than machines—and great singers.

In fact, both features define the new YouTube-driven efforts by Bradlee and Puddles. Songs like Shaggy's "It Wasn't Me," becomes a swinging Tom Jones-style piece; Meghan Trainor's "All About That Bass" becomes a sexy, slinky jazz tune; Tears for Fears' "Mad World" suddenly offers an opportunity for a bit of soft-shoe. All the songs feature old-school song-craftsmanship with crystal clear, sometimes stunning vocals.

"Sometimes the vocals in contemporary songs get buried in the mix or they're delivered in a way that makes it difficult to understand the words," Puddles wrote in an email to VICE. (He doesn't actually speak in public, and while the man behind the clown makeup can be identified easily with a Google search, he preferred to communicate in character, via the written word.) "Crooning the lyrics and bringing them to the forefront often makes the song more accessible to listeners. I get lots of comments from folks who are surprised that they can suddenly understand the lyrics to a song they've heard for years."

"You can strip it away from all the production—which tends to date the song when it was recorded —if you strip it away from all that stuff, there's a lot more flexibility in it," Bradlee says. "Songs are malleable, like Silly Putty."

That the rediscovering and recreating songs both new and old thrives on YouTube and on shows like AGT makes sense when you consider the very large role television has played in this trend, which began in earnest with American Idol. Musicians have been covering songs forever, but AI in 2002 was a juggernaut—and a music-consumption machine. After decades of the singer-songwriter model dominating the music scene, suddenly artists like Kelly Clarkson and Fantasia Barrino were getting famous based on their ability to thrill audiences with fresh versions of old songs like "Natural Woman" and "Summertime"—the latter song, of course, from "Porgy and Bess." And because the show emphasized vocal acrobatics, there was no hiding place for singers behind layers of effects and production.

Other singing competition shows followed, as did Glee in 2009—which put out a musical every week, almost all the songs familiar to the audiences who'd grown up during the '60s, '70s, and '80s.

Around the same time, Bradlee was failing in his ambitions to make a living as a jazz pianist. On a whim, though, he made a video of himself playing a medley of pop songs done in a ragtime style. While it didn't approach the viral levels of success he'd enjoy with later videos, the audience numbers were enough to keep him going under the Postmodern Jukebox banner, recruiting other musicians to make new, classic-sounding tunes out of modern hits.

The "Sweet Child O' Mine" was a hit at 9 million views. But it was PMJ's collaboration with Puddles—a cover of Lorde's "Royals"—that went truly stratospheric: The video has been viewed more than 21 million times to date.

Now Puddles and Bradlee churn out videos, separately, every few days. Puddles can be more experimental, with stunts like singing "Pinball Wizard" to the tune of "Folsom Prison Blues"—regularly earning hundreds of thousands of viewers and occasionally scoring a viral hit. Yagoda believes the site is critical to their artistic success.

"The video is real clear and has high production values, as opposed to what you might expect to see on YouTube," he tells VICE. "I think that's really important—it's spot-on in the technical things, which allows the interpretation to come through."

It's also allowed the musicians to make a living from their work.

"I've been kicking around from town to town for many years, singing my songs to the party people," Puddles writes. "But ever since YouTube came along, the party has grown immeasurably."

Bradlee agrees: "I think I came to this at the right time. Five years earlier, five years later, I think I would've missed out," he says. YouTube has "allowed me to go direct to fans, to bypass a record label. I have an unprecedented amount of control over the touring enterprise, recording, etc."

While Puddles is making the most of his "America's Got Talent" appearance after years of traveling with his own cabaret-style show, Bradlee tours constantly with a rotating "cast" of up to 60 collaborators that includes American Idol alumni like Haley Reinhart, Casey Abrams, Rayvon Owen, Blake Lewis, Joey Cook, and Von Smith. Other collaborators, like Morgan James, have branched out into making their own videos.

One benefit of their work? Young audiences are using PMJ, Puddles, and their peers to find their way back to the original Great American Songbook. Fans of hip-hop and indie music suddenly find themselves seeking out the music of the old masters.

"It's kind of a gateway to that stuff," says Bradlee. "That was how I learned music, and I wanted to share it with people. PMJ makes it digestible to people."

Some fans "tell me they'd never heard of Tony Bennett or Oscar Brown Jr. or Scott Walker until they heard me sing one of their songs," Puddles adds. "I can't wait for their minds to be blown as they dig deeper into the amazing catalogues of old-school artists like that."

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